Probe lock



Jan. 16, 1968 J. N. BOND 3,363,291

PROBE LOCK Filed March 21, 1966 INVENTOR J5me? A4 50M) ATTORNEY United States Patent 3,363,291 PROBE LOCK Joseph N. Bond, Commack, N.Y., assignor to Potter Instrument Company, Inc., Plainview, N.Y., a corporation of New York Filed Mar. 21, 1966, Ser. No. 536,036 4 Claims. (Cl. 24-449) ABSTRACT OF THE DISCLOSURE A latch-ring lock in which a lug extending inwardly from an outer sleeve engages the ring and lifts it into a plane perpendicular to the shaft axis permitting it to be moved up the shaft easily. Friction between the shaft and the latch ring permits the collar to be moved down the shaft easily.

This invention relates to a self-locking collar and, more particularly, to an improved self-locking collar which can be moved easily in either direction along a shaft on which it is mounted.

One object of this invention is the provision of a simple, inexpensive collar which locks onto a shaft automatically, yet can be moved easily with one hand in either direction along the shaft.

Another object of this invention is the provision of a self-locking collar which can be adjusted to tightly engage a shaft despite distortion of the operative looking member of the collar due to wear.

Briefly, this invention contemplates the provision of a collar in which one side of a latch-ring locking member is pivotally supported on the lip of an inner cup-shaped support. An outer cup-shaped sleeve telescopes over the inner member, and carries a lug which ext-ends through a slot in the wall of the inner cup and under a beveled edge on the other side of the latch-ring.

As in prior art devices which employ a latch-ring as a locking member, when the latch-ring of this invention is canted With respect to the axis of a shaft on which the collar is mounted, it frictionally engages the shaft and thereby automatically locks the collar to the shaft.

By grasping the outer sleeve in one hand, the collar can be moved down the shaft easily since friction between the shaft and the latch-ring urges the ring into a plane which is perpendicular to the shaft axis. Grasping the outer cup and urging it in the opposite direction along the shaft moves the outer cup at small distance relative to the inner cup. The lug on the outer cup lifts the latch-ring into a plane perpendicular to the shaft axis, thereby allowing the collar to move up the shaft easily as well as down.

Having briefly described this invention, it will be de scribed in greater detail along with other objects and advantages in the following detailed description of a preferred form which may best be understood by reference to the accompanying drawings, in which like reference numerals are used to indicate like parts in the various views, and in which:

FIG. 1 is a pictorial view of one embodiment of a collar constructed in accordance with the teachings of this invention, mounted on a vertical probe;

FIG. 2 is a sectional view of the collar shown in FIG. 1, showing the collar in a locked configuration;

FIG. 3 is a sectional view along the line 33 of FIG. 2;

FIG. 4 is a perspective detail view of the inner cup of the collar shown in FIG. 3;

FIG. 5 is a sectional view of the collar shown in FIG. 2 in an unlocked configuration; and

FIG. 6 is a plan view of an alternate embodiment of the invention which has a keyway to accommodate a rack.

3,363,291 Patented Jan. 16, 1968 More particularly referring now to FIG. 1 of the drawings, in a typical application a collar 10 constructed in accordance with the teachings of this invention, is mounted on a vertical probe 12 which passes freely through a bore 14 in a cross member 16, only a fragment of which is shown. A coiled compression spring 18, disposed between the cross member 16 and the lower surface of the collar 10, urges the collar 10 upwardly on the shaft 12 and automatically locks it to the shaft in a manner to be described hereinafter. With the collar 10 locked to the probe 12, the spring 18 supports the probe, allowing the probe to be moved easily upwardly and downwardly within a certain range. In order to establish a new range of movement, the collar 10 need only be grasped in one hand and moved up or down the shaft to a new position.

Referring now to FIGS. 2, 3 and 4 of the drawings, the annular self-locking collar 16 includes an inner cupshaped support 22 which telescopes into outer cup-shaped sleeve 24. The inner cup-shaped support 22 has an annular wall 26 and a centrally disposed bore 28, the diameter of which is slightly larger than the diameter of the probe 12. The outer cup-shaped sleeve 24 is similarly formed with annular wall 32 and a centrally disposed bore 34 equal in diameter to and axially aligned with bore 28.

The operative locking member of the collar 10 is a latch-ring 38 pivoted on the inner cup-shaped member 22 by means of a tab 36 which extends from the lock ring and rests in a notch 42 cut in the lip of the inner support. A tab 44, disposed diametrically opposite the tab 36, extends into a slot 46 cut in the wall 26 of the inner cupshaped member 22. The lower surface of tab 44 is beveled and, in the locked position shown in FIG. 2, it rests on a screw 48 which is screwed through the wall 32 of the outer cup-shaped sleeve 24.

The diameter of a centrally disposed bore 52 in the latch plate 38 is slightly larger than the diameter of probe 12. When the plane of the latch plate 38 is canted with respect to the axis of the probe 12, as shown in FIG. 2, the edges of the bore 52 frictionally engage the probe 12 and lock the collar 19 to the probe.

A small spring 54, the ends of which are embedded in the wall 26 of the inner cup-shaped member 22, is wrapped around a post 56 and urges the latch plate 38 into a canted position with respect to the axis of probe 12.

Pins 58 secured in the outer cup wall 32 fit loosely in slots 62 in the wall 26 of the inner cup and prevent the inner and outer cups from coming apart, while at the same time allowing relative movement between these members.

In operation, a downward force exerted by the probe 12 relative to the inner cup 22 cants the latch-ring 38, automatically locking the collar 10 to the probe. By grasping the collar 10 in the manner illustrated in FIG. 1, and moving it downwardly, while holding the probe 12, a frictional force develops between the probe 12 and the edge of bore 52 which moves the latch-ring 38 into a position (shown dotted in FIG. 2) in which the plane of the ring 38 is substantially perpendicular to the axis of the probe 12. With the latch-ring 38 in this position, the collar 10 moves easily along the probe 12. When the collar 10 has been moved to a desired position, the collar and probe are released and the downward force of the probe 12, cants the lock-ring 38, locking the collar to the probe.

When the outer cup 24 is grasped and moved upwardly with respect to the probe 12, the outer cup 24 moves a small distance relatively to the inner cup 22. The screw 48 lifts one side of the latch-ring 38, orienting the latchring in a plane which is perpendicular to the axis of the probe 12 as shown in FIG. 5. With the latch-ring 38 in this position, the collar 10 can be moved up the probe 12 easily. When the collar and probe are released, the outer cup 24 drops relatively to the inner cup 22, and the latchring cants in the manner previously described, automatically locking the collar it? to the shaft.

In certain instances, repeatedly changing the position of collar 16 on the shaft 12 causes the bore 52 to become enlarged slightly'so that it no longer tightly engages the shaft 12. Screw 48 provides a means of compensating for such wear. Backing the screw 48 out of the slot 46 a small distance permits a worn lock-ring to tightly engage a shaft, since the latch-ring 38 will be canted at a more extreme angle when the beveled lower surface of tab 44 contacts the screw 48.

In certain applications it may be desirable to determine the position of the probe 12 by means of a rack secured to the probe which engages a suitable pinion type transducer. As indicated in FIG. 6, aligned keyways 64 can be cut in the outer cup 24, inner cup 22 and latchring 38 to accommodate the rack secured to the probe 12. Such a key 64, of course, does not interfere with or alter the operation of the collar 14).

This invention may be variously modified and embodied within the scope of the snbjoined claims.

What is claimed is:

1. A self-locking collar for a shaft comprising in combination;

a cup-shaped sleeve, 7

a cup-shaped support member,

said sleeve surrounding said support member and moveable relative thereto in a direction parallel to the longitudinal axis of the shaft,

a latch-ring pivotally supported by said support memher,

said latch-ring moveable between a first position frictionally engaging a shaft and a second position substantially clear of the shaft, and

an inwardly extending lug carried by said sleeve for a moving said latch-ring to said second position as said sleeve moves relative to said support member, said lug contacting a region of said latch ring when said ring is in said first position.

2. A self-locking collar as in claim 1 wherein said region is beveled and said lug is a screw, whereby the cant of said latchring in said first position may be adjusted to compensate for distortion of the latch-ring.

3. A self-locking collar as in claim 2 further including a spring which urges said latch-ring to said first position.

4. A self-locking collar as in claim 3 further including a keyway passage through said collar for accommodating a rack on the shaft.

References Cited UNITED STATES PATENTS 600,864 3/ 1898 Glover 292-306 1,412,857 4/1922 Gale. 1,619,589 3/ 1927 Steenrod.

DONALD A. GRIFFIN, Primary Examiner.

A. RUDERMAN, Assistant Examiner. 

